As mobile communication devices such as mobile phones, smart phones, and tablets become more capable, they are more frequently being used as a substitute for more traditional platforms. Thus, for example, a mobile device may now be used for banking, business communications, and other functions that were previously accomplished via a traditional desktop computer. While this new freedom has many benefits for users, it also creates new risks.
For example, due to their portable nature, mobile devices are less secure; that is, they are more easily compromised by thieves or other unauthorized parties. To combat this, many users configure their mobile devices to require authentication prior to granting access. Re-authentication may be required after a certain period of inactivity or after the user puts the device into an inactive state.
A number of authentication mechanisms are available, e.g., voice recognition authentication, password authentication, pattern authentication, facial recognition authentication, and so on. However, for most authentication mechanisms, there will be situations in which the selected mechanism is impractical. For example, in a dark theater, facial recognition authentication may be impractical, and in a loud train station, voice recognition authentication may be impractical.
While the present disclosure is directed to a system that may eliminate some of the shortcomings noted in this Background section, it should be appreciated that any such benefit is not necessarily a limitation on the scope of the disclosed principles or of the attached claims, except to the extent expressly noted in the claims. Additionally, the discussion of technology in this Background section is reflective of inventor observations or considerations, and is not intended to be admitted or assumed prior art as to the discussed details. Moreover, the identification of the desirability of a certain course of action is the inventors' observation, and should not be assumed to be an art-recognized desirability.